Releasable balloon decoys



1966 E. D. FISHER 3,229,290

RELEASABLE BALLOON DECOYS Filed March 6, 1953 4 Sheets-Sheet 1 INVENTOREVAN D. FISHER TTORNEYS Jan. H, 1966 E. D. FISHER RELEASABLE BALLOONDECOYS 4 Sheets-Sheet 2 Filed March 6, 1953 INVENTOR EVAN D. FISHERATTORNEYS Jan. 11, 1966 Filed March 6, 1953 E. D. FISHER RELEASABLEBALLOON DECOYS 4 Sheets-Sheet 5 INVENTOR EVAN D. FISHER ATTORNEYS Jan.11, 1966 E. D. FISHER RELEASABLE BALLOON DECOYS 4 Sheets-Sheet 4 FiledMarch 6, 1955 United States Patent 3,229,290 RELEASABLE BALLDON DECOYSEvan D. Fisher, 9014 Spring Hill Lane, Chevy Chase, Md. Filed Mar. 6,H53, Ser. No. 340,935 6 Claims. (Cl. 343l8) (Granted under Title 35, US.Code (1952), sec. 265) The invention herein described may bemanufactured and used by or for the Government of the United States ofAmerica for governmental purposes without the payment of any royaltiesthereon or therefor.

The present invention relates to a decoy balloon launching system, andmore particularly to an automatic balloon inflating and releasing systemadapted for launching radar decoys from surface vessels.

In the rapid advancement of modern warfare it is frequently advantageousto position radar decoys at predetermined locations at sea, and it hasbeen practicable to employ balloons carrying a reflective material forthis purpose, usually launched from a surface vessel. In general, theprior systems for placing such decoy balloons in operation from aboard avessel at sea has been to manually inflate the balloons from gas flasksand to drop them over the side to the surface of the water. In case ofhigh winds, or other adverse weather conditions, balloon launchingoperations had to be discontinued until sufliciently calm conditionsprevailed to prevent danger to members of the launching crew of beingswept overboard. Also, such adverse weather conditions usually preventpresent inflating and releasing balloons without rupturing them as theyare subjected to weather on the vessels deck. The balloons presentlyutilized are approximately six feet in diameter and when subjected tohigh wind pressures, the neck of the balloon when attached to the nozzleof the gas flask or otherwise anchored is placed under high stressesthat quickly ruptures the balloon neck. Furthermore, large banks ofhelium flasks are required on board the vessel thereby occupying spaceusable for critically needed gear.

The present invention enables personnel aboard a surface vessel tolaunch radar decoys quickly and efiiciently without danger to thepersonnel or rupture of the balloons in any Weather encountered. Theballoon inflating system provides an automatic method for launchingradar decoys at any predetermined location at sea which will givesimulated signals to radar of submarines, surface ships, and aircraft.The entire system including the radar decoys is packed in a containerwhich occupies very little space and consequently enables a vessel tocarry a large number of these containers without jeopardizing spacerequirements. The decoy balloon is launched by simply dropping thecontents of a container into the water, eliminating the necessity ofinflating and releasing the balloon fro-m the hazardous deck of thevessel. The action of the water on a chemical contained in the unitinflates the balloon to carry the reflective material to its operationalposition.

The system is vented to the sea so that a water-activated chemicalwithin the system may automatically generate gas to inflate the balloon.It is impractical to employ a rigid hermetically sealed tank to supportthe inflation system while the balloon is inflating, because of its sizeand weight, so that a non-rigid structure or a float bag as it is calledherein, is provided which successfully operates on the surface of thewater. The gas generated by the wateractivated chemical escapes into thefloat bag to maintain the system at water surface level and to inflatethe balloon which is connected to the float bag by a one-way valve. Theone-way valve is responsive to the water level within the float bag andserves to maintain the inflation system on the surface of the wateruntil the water-activated chemical is expended, at which time theballoon is automatically released. A solid float structure is attachedto the balloon to anchor it at a predetermined altitude by means of aconnecting line to which are attached the reflective materials which actas the radar decoys. Each decoy comprising an elongated reflectingmaterial such as a strip of thin aluminum foil.

An object of the present invention is the provision of a ballooninflating and releasing system for launching airborne radar decoys froma surface vessel.

Another object is to provide a balloon inflating and releasing systemwhich operates automatically when dropped into the water.

A further object is to provide a balloon launching sys tem which remainson the surface of the water while the balloon is being automaticallyinflated.

Still another object of the invention is the provision of a balloonlaunching system that automatically releases the inflated balloon fromthe gas generator.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings in which like referencenumerals designate like parts throughout the figures thereof andwherein:

FIG. 1 is a perspective view of a preferred embodiment of the inventionin operation;

FIG. 2 is a side view, partly in section, of the embodiment of theinvention shown in FIG. 1;

FIG. 3 is a vertical cross sectional view of the preferred embodiment ofthe gas generator shown in FIG- URE 2;

FIG. 4 is a plan view of a section of the preferred embodiment taken onthe line IV-1V of FIG. 2, looking in the direction of the arrows;

FIG. 5 is a perspective view of the one-way valve; and

FIG. 6 is a side view, partly in section, of the preferred embodiment ofthe invention as it is packed for launching.

Referring now to the drawings, there is shown in FIG. 1 a preferredembodiment as it appears in use comprising a balloon 11 composed of aflexible resilient material, which is impervious to gas such as pure gumor the like, a resilient impervious float bag 13 connected to theballoon in a manner to be described later, a wooden float 15, and a line17 securing the balloon to the wooden float and supporting streamers 19of a reflective material, such as thin strips of aluminum foil or othermaterials having similar characteristics.

In FIG. 2, the preferred embodiment is shown immediately after beingdropped into the water from a surface vessel and in the process ofinflating the balloon 11. The balloon is provided with a neck 21 whichis secured to a neck piece 23 by a lock ring 25 forcibly depressing acircumferential portion of the neck 21 into a neck piece groove 27, thelock ring being preferably covered with an impervious tape 29 to preventthe possibility of rupturing the balloon 11 by the ring 25. The neckpiece 23- is provided with a internal flange 31 and, longitudinallyspaced therefrom, with internal threads 33 which threadably engageexternal threads 35 of a coupling 37 which interconnects the balloon 11and the float bag 13. Between the flange 31 on the neck piece 23 and anend face 39 on coupling 37 is supported a oneway or check valve 41,later to be described, and lateral flanges 43 and 45 of a cylindricalshort housing 47 and a cylindrical long housing 49, respectively.

The short housing 47 protrudes into the balloon 11 and serves to preventthe balloon from completely collapsing and interfering with theoperation of the check valve 41. The short housing is formed with aplurality of longitudinally spaced apertures 51 in diametrically opposedrelationship and an end 53 reduced in diameter, as shown in FIG. 2, andfitted with a rubber grommet 55 to protect the balloon. The long housing49 protrudes into a float bag 13,, to be later described, and is formedwith a plurality of longitudinally spaced apertures 57 in diametricallyopposed relationship, for a purpose to be later described. The lower endof the long housing 49 is fitted with a cap 61 having a bore 63 servingas a guide for a longitudinally movable float arm 65. The float armconsists of a thin wall tubing with solid screw inserts 67 and 68 ateach end thereof and a limit disc 69 fixedly secured thereto to limitthe downward movement of the float arm 65. The lower end 68 of the floatarm 65 is attached to a float 73, and the upper end 67 has threadedthereon a hexagonal valve member 70 provided with a rubber gasket 71 ofa predetermined diameter secured thereto and facing the check valve 41.The hexagonal valve member 70 has a cross-corner diameter slightly lessthan the inside diameter of the cylindrical long housing 49 to providesuflicient clearance for the longitudinal movement of the float arm 65within the long housing 49. The rubber gasket 71 of the valve member 70serves to seal the check valve 41 when the float bag 13 extends from thewater less than a predetermined length needed to support the decoy.

As previously mentioned, the float bag 13 is of impervious material, andserves to retain gas therein where the washer 71 is forced upward by thefloat 73. The float bag is elevated by the gas trapped therein untilsuch time as the apparatus is at a suitable height above the water. Thefloat 73 then opens the passage to the balloon 11 and allows the gas toenter. However, if the water level in the float bag 13 again rises, thepassage is again closed.

The check valve 41 consists of a valve disc 75 having a plurality ofapertures 77 therethrough being juxtaposed to a valve gasket 79. Thegasket 79 consists of a upwardly extending hinge lid 81, which isadapted to completely cover the apertures 77 when in a closed position,and a weight 83 secured to the hinged lid to provide added weightthereto and thereby increase the inertia of the hinged lid to the flowof gas into the balloon 11. The check valve 41 is rigidly supportedbetween the flanges 43 and 45 of short housing 47 and long housing 49,respectively, by the threaded engagement of the coupling 37 with theneckpiece 23. The float arm 65 is adapted to longitudinally reciprocatewithin the long housing 49 between the limits determined by the limitdisc 69 in a downward direction and in an upward direction by the rubbergasket 71 of the valve member 70 abutting the thin valve disc 75 to sealthe apertures 77.

The coupling 37 is formed with a circular flange 85 projecting in ahorizontal direction and a groove 87 adapted to receive the line 17. Thefloat bag 13 is cylindrically shaped and of a predetermined length withthe upper end tapered to a narrow circular opening which is fixed to thecircular flange 85 of the coupling 37, by any securing material, such ascement. The lower open end 89 of the float bag 13 is provided with agrommet 91, composed of several loops of piano wire, or the like.

The grommet S-1 serves as a stifliening member for the resilient floatbag as as to maintain the lower portion of the float bag 13 in acontinuously open or inflating position.

At a predetermined distance above the grommet 91, the float bag 13 isprovided with a number of apertures 93 equally spaced about theperiphery. Each aperture 93 is provided with a rubber grommet mountedtherein to support a weight 95 by any securing device, such as a screwand nut, or the like. The weights 95 aid in maintaining the float bag 13in a vertical position when on the surface of the water. At a setdistance above the grommet 91 the float bag is provided about itsperiphery with a number of equally spaced apertures 97 each adapted toreceive the threaded end 98 of a folding arm 99 of the spider 100. Eachaperture 97 is provided with a rubber grommet to support the threadedend 98 by any suitable securing device, such as the concentric nuts 101,or the like. Each folding arm 99 is provided with a bore 103 near theinner end thereof, so that each folding arm may be pivotally coupled tothe hub 105 of the spider by a wire loop 107 passing through the bores103 and through the hub 105. The hub is constructed so that each foldingarm is restrained from any upward movement, relative to the hub, bystops 109; however, the folding arms are free to pivot downward relativeto the hub to facilitate packing of the float bag 13. The hub 105 isprovided with a plurality of apertures 111 to decrease the overallweight of the hub and to facilitate the attachment of a wireholder 113to the hub. The wireholder is looped through two adjacent apertures 111and extends downward into a gas generator 115 to secure it to the hub105. The length of the wireholder 113 is adjusted so that the greaterpart of the gas generator is covered by the float bag 13.

As shown in FIGURE 3, the gas generator 15 comprises a cylinder 117secured to a base plate 119 as by welding, or the like. The wireholder113 extends down along the inside surface of the cylinder 117 and acrossthe upper face of the base plate 119, with a disc 121 be tween theportion of the wireholder lying across the base plate and apredetermined portion of a water-activated chemical 123, such as lithiumhydride, or the like. The chemical 123 is compacted within the gasgenerator under a pressure which serves to control the generating rateof the gas, and to maintain the wireholder 113 firmly between the baseplate 119 and the disc 121 until the chemical 123 is substantiallyexpended. A canister cover 125 is secured to the base plate 119 by anysuitable securing device such as the screw 127, or the like. Thecumulative weight of the cylinder 117, base plate 119, disc 121, andcanister cover 125 is such that the balloon inflating system will remainon the surface of the water until the chemical 123 is expended and thegas generator 115 is released from the wireholder 113, whereupon theballoon 11 elevates the system to a predetermined altitude, ashereinafter explained.

Where lithium and calcium hydride are reacted with water, they form thecorresponding hydroxides which can solidify over the surface of thehydride. However, where the reaction takes place in an adequate supplyof water with agitation, these deposits are dispersed into the water. Inthe present invention, it has been found that the evolution of gas froma submerged chemical container supplies suflicient agitation, where thechemical is exposed to water only at the top, so that the evolved gas iscontinuously passing through the Water causing the reaction.

The steam which may be formed by the reaction of the hydride with wateris condensed in passing through the water above the chemical container.Water is therefore prevented from entering the balloon by maintainingthe balloon vent a suitable height above the water as previouslyexplained, and by passing the gas through water before it enters thefloat bag 13.

The line 17, securely fastened at the upper end about the groove 87 ofthe coupling 37, has the lower end fastened to the wooden float 15. Thewooden float is constructed of a predetermined weight to maintain theelevated balloon 11 captive and not free to soar into the atmosphere soas to lose its eflectiveness as a radar decoy. The reflective material19 consists of a plurality of thin streamers or strips 127 attached tothe line 17 at a set distance between the coupling 37 and the woodenfloat 15.

In FIG. 6, the preferred embodiment of the invention is shown packed ina canister 129 to facilitate handling and storage aboard a vessel. Thecanisters can be stored in a vessel in any available space withoutrequiring special protection to the water-activated chemical 123, theballoon 11, or the reflective material strips 127. The plurality ofstrips 127 are rolled, one on top of the other, about the periphery ofthe wooden float which is placed within the canister 129 adjacent thefolded float bag 13 and the deflated folded balloon 11. The deflatedballoon is covered with an ordinary paper bag 131 to protect the balloonfrom any injury caused by the movement of the balloon within thecanister 129, especially as to excessive friction between the balloonand the inside surface of the canister or the reflector strips 127. Thecanister cover 125 is secured to the canister 129 by a removable metalstrip 133 which overlaps the edges of the canister and the canistercover, and secured thereto by any suitable attaching means as soldering,or the like. The metal strip 133 is provided with a metal ring 135 tofacilitate removal of the metal strip when it is desired to launch thedecoy system. The canister is provided with a handle 137 to facilitatehandling of the system.

In operation, the balloon inflating system is launched from a surfacevessel in the simple operation of removing the metal strip 133, whilegrasping the handle 137, and allowing the contents of the canister 129to fall into the water. As soon as the system strikes the water, the gasgenerator 115 sinks below the surface because of its weight, thuscausing the water to come in contact with the chemical 123 and toquickly generate gas. The weights 95 will cause the float bag 13 tosubstantially cover the gas generator and direct the flow of gas to thefloat bag 13. If the water level within the float bag 13 reaches thefloat 73 and commences to rise further, the float arm 65 will be movedupward by the rising of the float until it seals the apertures 77 of thecheck valve 41 which prevents the flow of water into the balloon 11. Assoon as sufficient gas has been generated within the upper portion ofthe float bag to lower both the water level and the float 73, the gaswill flow through the apertures 57 of the long housing 49 past the valvemember 70 and through the apertures 77 of the check valve to raise thehinged lid 81, and then through apertures 51 and end opening 53 of theshort housing into the balloon 11. In this manner, as long as the waterlevel within the float bag is low enough to prevent the float 73 frommoving upward to close the check valve, the gas in the upper portion ofthe bag 13 will flow into the balloon 11 to inflate it.

The float 73 controls the amount of gas in the upper portion of thefloat bag 13 to maintain the balloon inflating system on the surface ofthe water until the balloon is sufficiently inflated and the chemical123 is completely expended to release the gas generator from the floatbag 13. The generated gas accumulates in the float bag and is allowed toflow into the balloon 11 only when the volume of gas in the float bag 13exceeds that required to maintain the system on the surface of thewater. As soon as the accumulation of gas in the float bag 13 is loweredto the point where the water level raises the float 73, the flow of gasinto the balloon 11 is stopped by means of the float arm 65 until theaccumulation of gas in the float bag 13 lowers the water level and thefloat, so that any excessive accumulation of gas may again commence toinflate the balloon 11. The process of generating gas to maintain thesystem buoyant on the surface of the Water and to inflate the balloon 11with the excess gas from the float bag 13 continues until the chemical 123 is completely expended.

The gas generator is released from the wireholder 113 when the chemical123 is completely activated, since the wireholder is merely held thereinby the compressed chemical. As soon as the wireholder releases the gasgenerator, it sinks to the bottom while the inflated balloon 11 elevatesto an altitude determined by the length of the line 17.

As the balloon 11 ascends, the line 17 and the reflector strips 127 areunrolled from the wooden float 15 to assume the operational altitude asshown in FIG. 1.

For the purposes of illustration of one embodiment of the presentinvention, strips of aluminum foil 127 are supported above the surfaceof the water by a SOD-gram weather balloon 11 of natural latex with acapacity of 45 cubic feet. The float bag 13 has a length of 38 inchesand a diameter of 8 inches at the lower open end, and constructed fromnylon 0.9 ounce per square yard medium tenacity yarn coated on bothsides with neoprene. The float bag material has a total weight of 5ounces per square yard and tensile strength of 40 pounds per inch. Theweights consist of four lead fishing sinkers, each weighing one ounce.The gas generator 115 has 1% pounds of 93% pure lithium hydridecompressed within the cylinder 117 by a pressure of twenty tons.

Various modifications are contemplated and may obviously be resorted toby those skilled in the art without departing from the spirit and scopeof the invention, as hereinafter defined by the appended claims, as onlya preferred embodiment thereof has been disclosed.

What is claimed is:

1. A balloon inflating and releasing unit for radar decoys comprising aballoon having a vent, a resilient float bag sealed to said vent, acheck valve interposed between said balloon and said float bag, a woodenfloat, a line connecting said wooden float to said float bag, a gasgenerator releasably secured to said float bag and being partiallyenclosed therein, and valve means responsive to the water level in saidfloat bag for preventing passage of gas from said float bag and saidballoon when the height of the float bag above the water is below apredetermined level.

2. The invention as defined in claim 1 but further characterized by aplurality of reflectors secured to said line for operation as radardecoys.

'3. A balloon inflating and releasing system comprising a balloon, a gasgenerator producing a lighter-than-air gas when submerged in water, afloat bag connected to said balloon and said gas generator, a checkvalve coupling said balloon and said float bag, said gas generator beingimmersed in water and operating within said float bag to thereby inflatesaid balloon.

4. The invention as defined in claim 3 but further characterized by saidgas generator comprising a cylindrical container having an open upperend, a water-active chemical compressed under high pressure into saidcontainer, a wireholder having a first end extending into said containerand maintained therein by said water-active chemical, and saidwireholder having a second end secured to said float bag whereby afterthe water active chemical is expended the first end of said wireholderis released and the gas generator sinks to the bottom and said balloonand said buoyancy means use out of the water.

5. A balloon inflating and releasing unit for launching radar decoysfrom a surface vessel comprising, a balloon, a gas genera-tor containingan expendable chemical releasing a lighter-than-air gas when exposed towater, reflecting material attached to said balloon, and means includingthe expendable chemical releasably attaching said balloon to saidgenerator, said attaching means including means operative automaticallyresponsive to substantially complete expendature of said chemical forreleasing said balloon from said generator.

6. A radar decoy launching unit comprising a balloon, an imperviousfloat bag, a one-Way check valve connecting the balloon to the floatbag, a gas generator containing an expendable chemical releasing alighter-than-air gas when exposed to water, and means including theexpendable chemical for releasably attaching the generator to the floatbag, said attaching means including means opera- References Cited by theExaminer UNITED STATES PATENTS 2,334,211 11/1943 Miller v102--7 X2,470,783 5/1949 Mead 343l8 2,489,337 11/1949 Sperling 34318 BENJAMIN A.BORCHELT, Primary Examiner.

SAMUEL BOYD, ARTHUR M. HORTON, Examiners.

tive by substantially complete expenditure of the chemical 10 S. H.GOLDMAN, R. W. ERICKSON, Assistant Examiners.

5. A BALLOON INFLATING AND RELEASING UNIT FOR LAUNCHING RADAR DECOYSFROM A SURFACE VESSEL COMPRISING, A BALLOON, A GAS GENERATOR CONTAININGAN EXPENDABLE CHEMICAL RELEASING A LIGHTER-THAN-AIR GAS WHEN EXPOSED TOWATER, REFLECTING MATERIAL ATTACHED TO SAID BALLOON, AND MEANS INCLUDINGTHE EXPENDABLE CHEMICAL RELEASABLY ATTACHING SAID BALLOON TO SAIDGENERATOR, SAID ATTACHING MEANS INCLUDING